Tom Corbett and his friends, Astro and Roger Manning, participate in the most daring undertaking in all space history. While on an experimental trip in the Polaris to test out some new equipment they and Captain Connel learn of a scheme of a pair of notorious space freebooters to steal the rich mineral resources of one of the planet Tara's small satellites. To foil the scheme the members of the Polaris crew themselves land on the satellite with the daring plan to blast it out of Tara's orbit and into Earth's orbit where its valuable mineral wealth may replenish Earth's shortages.